Intubation is the placing of a rigid or semi-rigid tube in a body passageway for varying periods of time ranging from a few hours to permanent positioning. Mostly intubation involves the use of such a tube in the respiratory tract to ensure respiration by providing a clear upper airway. Such intubation devices, however, are not limited in use in the respiratory tract, but find application in other body passages wherein a clear pathway is desired. Moreover, such intubation devices find use in various portions of the respiratory tract.
Endotracheal tubes are frequently used for the primary purpose of ensuring that a patient's airway remains clear, which secondarily provides access to the bronchial tree for the aspiration of secretions. However, by the fact that the intubation device is a tube placed within the body passageway, the natural lumen or size thereof is necessarily reduced, although the narrower tube lumen is ensured to be clear. This leads to a specific problem which is brought on by the provision of an inflatable cuff near a distal end of the intubation device which is inflated once the tube is intubated for securely holding the tube in place and for sealing the tube to the body passageway so that all of the air passing to and from the patient's lungs must pass through the tube. The inflated cuff, in position, forms a space above the cuff and between the intubation device and the body passageway within which secretions and bacteria, or the like, will accumulate. Although the accumulation of the secretions is not particularly beneficial, the seal of the inflatable cuff advantageously prevents the accumulated secretions from passing into the patient's lungs so long as the cuff remains fully inflated. However, the problem is that the secretions that build up within this space may also cause harm the patient.
When the intubation device is intubated within the respiratory tract, the tube passes into the trachea through the epiglottis, and as a result the epiglottis cannot then close. Thus, saliva from the mouth can pass and become trapped in the larynx and trachea. Moreover, other secretions that are produced by the body are trapped as well. The large amount of secretions and bacteria that collect in the space above the cuff can be disadvantageously drawn into the patient's lungs during coughing, cuff deflation, or extubation (i.e., tube removal). This not only presents an immediate danger to the patient's ability to breath, but is believed to substantially increase the chance that the patient will develop aspiration pneumonia.
Thus, it has become desirable to find ways for removing the secretions and bacteria that collect above the cuff during the time period of intubation. Typically, such removal includes the application of suction to the above-the-cuff region for the removal of collected secretions. The initial solution was simply to periodically insert a suction catheter along with the intubation device once intubated and sealed by the cuff, to suction out accumulated secretions. As a modification to this procedure, it is presently known to provide an intubation device including an integrally formed suction catheter with an opening in the above-the-cuff region through which periodic or constant suction can be applied for removal of secretions after intubation.
A further modification and example of a combination intubation device with a separate channel to facilitate suction is described in U.S. Pat. No. 4,607,635 to Heyden. The endotracheal tube of Heyden comprises an intubation tube having an inflatable cuff near its distal end, wherein an elongated channel or passageway is provided along the length of the main tube and extends from the proximal end of the main tube to the cuff. Furthermore, the channel is provided with a plurality of ports along its entire length which define various points for suction to be applied along the tube. However, in operation, it is necessary to insert a suction catheter within the channel which when moved along the channel draws secretions into the suction catheter through each of the ports of the channel. The operation of this type of endotracheal tube disadvantageously causes an increase in patient discomfort associated with insertion and removal of the suction catheter as well as an increased tracheal irritation that results from suction being applied along the length of the trachea through the various ports. Additionally, it is necessary to regulate the insertion of the catheter and to control the depth thereof since unintentional overinsertion of the catheter could damage or puncture the cuff.
Although the Heyden '635 endotracheal tube does provide for an adjustment regarding the axial direction of the intubation device and the body passage, it has been found to be inadequate with regard to suctioning of accumulated secretions because it does not provide for any radial displacement just above the cuff. This has been found to be particularly important since the large majority of secretions that accumulate collect near the cuff along the tracheal wall in the region above the cuff. This is caused because of the general tendency of the secretions to flow toward the cuff due to a typical patient's orientation, that is downwardly toward the cuff, and additionally because the inflation of the cuff causes an expansion of the body passageway at the cuff which consequently enlarges the space formed just above the cuff in the radial sense. As a result, most secretions collect in this enlarged area. With the Heyden '635 device, the application of suction near the cuff is limited to the end port of the channel guiding the suction catheter so as to permit suction only very near the tube sidewall of the intubation device. This point of suction has been found to be inadequate in that all of the accumulate secretions cannot be removed. Granted, the inflation or deflation of the cuff will somewhat radially move and position the ports in the channel; however, there can be no radial adjustment once the intubation device is put in place by the inflated cuff, since any attempted movement would defeat the purpose of the cuff in that secretions would pass into the patient's lungs. Thus, the Heyden '635 device is unsuitable for the removal of the large amounts of secretions and bacteria that accumulate in the intubated pathway of a patient, particularly in the region above the cuff nearby the cuff.
A further modification to the above-described Heyden device is disclosed in U.S. Pat. No. 4,637,389 also to Heyden. The purpose of the modified intubation device is to provide a somewhat concealed channel on the intubation device but which functions similarly to the aforementioned Heyden device. Likewise, the channel includes a plurality of ports along the length of the tube and requires the insertion of a suction catheter to remove secretions via each port. The purpose is to protect the suction catheter from the direct contact with the intubated pathway to apparently reduce the aforementioned trauma and discomfort along the tracheal passageway. Once again, such a device is insufficient for effective removal of secretions that accumulate above and near the cuff, since there is no provision of any means to permit the application of suction at radially adjustable positions.
Other devices are available for removal of unwanted substances that may accumulate above the cuff in an intubated passageway of a patient. For example, for removing smoke that results in laser surgery, U.S. Pat. No. 4,632,108 to Geil discloses an endotracheal tube including an opening formed on the exterior of the tube above and adjacent the inflatable cuff at the distal end of the tube. In this case, a lumen is used to connect the opening to a smoke removal tube for removal of accumulated smoke in the region above the cuff. While such is suitable for that purpose, that is smoke removal, such a device need not be provided with the capability to position the opening in a close proximity to the tracheal wall for adequate removal of secretions and bacteria
Consequently, there is a need for an endotracheal tube that can effectively remove a large amount of secretions and bacteria that accumulate in the intubated pathway of a patient, and in particular, that accumulate in the region just above the cuff.